1. Field of the Invention
The present invention relates to a ventilation system for an underground structure, and more particularly to, a ventilation system for an underground structure which can internally supply fresh outdoor air by individually sucking and discharging air through fans of underground shafts in the underground structure such as an underground parking lot, underground warehouse, subway space, underground sporting place and underground hangar.
The ventilation system for the underground structure cuts down initial expenses for installing air supply/exhaust fans, fan rooms, large fans and an apparatus room, efficiently uses the underground space, reduces noises, cuts down maintenance expenses, and optimizes ventilation in the underground structure, by sucking fresh outdoor air and discharging used air on each floor with a low price and a simple structure.
2. Description of the Related Art
In general, a high-rise apartment building or high-rise building has an underground parking lot for conveniences of residents or tenants, and also has an underground warehouse in some cases. Military installations are installed underground for security.
However, air circulation is not efficiently performed by natural ventilation in the underground structure such as the underground parking lot and underground warehouse of the building and the underground military installations. Exhaust gases and other residual gases of vehicles are harmful to users. Therefore, air circulation is performed by forcible ventilation.
For example, in the underground parking lot, as illustrated in FIG. 1, shafts 1 are formed to pass through the underground parking lots on a few floors, air supply fan rooms 2 for supplying air and air exhaust fan rooms 3 for exhausting air are formed on each floor, air supply fans 2a for supplying air into the underground parking lot are installed in the air supply fan rooms 2, and air exhaust fans 3a for exhausting air from the underground parking lot are installed in the air exhaust fan rooms 3. In FIG. 1, the air supply fan rooms 2 and the air exhaust fan rooms 3 are disposed in the vertically identical positions on each floor, which is different from the real structure.
In the underground parking lot, various fans and ducts are installed to form passages between the air supply fans 2a and the air exhaust fans 3a, thereby efficiently discharging exhaust gases or other harmful gases of vehicles.
However, the air supply fans and the air exhaust fans are large-sized, to require fan rooms having a predetermined space. Accordingly, initial expenses are increased and the space of the parking lot is not efficiently used. Moreover, a lot of power is needed for the operation, noises are seriously generated, maintenance and repair expenses are increased, and the indoor environment is deteriorated.
On the other hand, ‘Ventilation system for underground structure’ applied for registration under Patent Application No. 10-2000-0085060 by the present applicants shows the improvements of the conventional ventilation system for the underground structure described above. FIG. 2 illustrates the ventilation system for the underground structure.
The ventilation system for the underground structure includes a duct 4 vertically installed along a shaft 1 of the underground structure, a fan 5 installed in the lowermost portion of the duct 4, for sucking air from the shaft 1 and supplying air to the duct 4, secondary nozzles 7 installed in openings formed on the wall of the shaft 1 in the underground structure side, and primary nozzles 6 installed in the duct 4 toward the centers of the secondary nozzles 7. It is intended to overcome the disadvantages of the conventional ventilation system.
However, the ventilation system is installed by connecting the nozzles to each fan, which requires a lot of power of the fans. The fans have a relatively large volume, and thus are not easily installed. In addition, noises are seriously generated. In case the fans are not operated, the whole ventilation system is stopped. That is, the whole control operation thereof is not easy.